Food warming oven



FIG. 1 is a front perspective view of a food warming oven showing our new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a left side elevation view thereof, the right side being identical; and,

FIG. 6 is a rear elevation view thereof. 

The ornamental design for a food warming oven, as shown. 